The most commonly used system to stage pancreatic cancer is the TNM system. It was developed by the International Union Against Cancer and the American Joint Committee on Cancer (AJCC).

The first step in staging is to find the value for each part of the TNM system. Here is what the letters stand for in the TNM system:

• T refers to the size of the tumor in the pancreas and if it has grown into nearby tissues.
• N refers to whether any lymph nodes in the area of the original tumor have cancer in them.
• M refers to whether the cancer has spread ( metastasized) to other, distant organs in the body, such as the liver or lungs.

Numbers or letters after T, N, and M provide more details about each of these factors. There are also 2 other values that can be assigned:

• X means the provider does not have enough information to tell the extent of the main tumor (TX), or if the lymph nodes have cancer cells in them (NX).
• 0 means no sign of cancer, such as no sign of spread to the lymph nodes (N0).

Stage groupings are determined by combining the T, N, and M values from the TNM system. These groupings give an overall description of your cancer. A stage grouping can have a value of 0 or of Roman numeral I through IV (1 through 4). The higher the number, the more advanced the cancer is. Letters and numbers can be used after the Roman numeral to give more details.

To arrive at the stage of your cancer, your healthcare provider first assigns numbers for the T, N, and M groups. These numbers are then combined in a process called stage grouping to give the cancer an overall stage. The lower the number, the less the cancer has spread. The higher the number, the more the cancer has spread.

These are the stages groupings of pancreatic cancer and what they mean:

Stage 0 . The tumor is only in the top innermost layer of cells lining the pancreatic duct. It has not invaded the deeper layers or spread anywhere else. This may be called pancreatic cancer in situ.

Stage I . The cancer has not spread to organs in other parts of the body. This stage is divided into 2 groups:

• Stage IA . The cancer is only found inside the pancreas. It’s no larger than 2 cm (centimeters) across.
• Stage IB . The cancer is only found inside the pancreas. It’s more than 2 cm but less than 4 cm across.

Stage II . The cancer has not spread to organs in other parts of the body. This stage is divided into 2 groups:

• Stage IIA . The cancer is only found inside the pancreas. It’s more than 4 cm across. It has not spread to nearby lymph nodes.
• Stage IIB . This stage can be any one of the following:
  • The cancer is only found inside the pancreas. It’s no larger than 2 cm across. It has spread to no more than 3 nearby lymph nodes.
  • The cancer is only found inside the pancreas. It’s more than 2 cm but less than 4 cm across. It has spread to no more than 3 nearby lymph nodes.
  • The cancer is only found inside the pancreas. It’s larger than 4 cm across. It has spread to no more than 3 nearby lymph nodes.

Stage III . The cancer has not spread to organs in other parts of the body. This stage can be any one of the following:

• The cancer is only found inside the pancreas. It’s no larger than 2 cm across. It has spread to 4 or more nearby lymph nodes.
• The cancer is only found inside the pancreas. It’s more than 2 cm but less than 4 cm across. It has spread to 4 or more nearby lymph nodes.
• The cancer is only found inside the pancreas. It’s larger than 4 cm across. It has spread to 4 or more nearby lymph nodes.
• The cancer has grown outside the pancreas and into large blood vessels that are nearby. It may or may not have spread to nearby lymph nodes.

Stage IV . The cancer has spread to organs further away from the pancreas. These might include the liver, lining of the abdomen (called the peritoneum), bones, or lungs.

Healthcare providers use the TNM system to formally stage pancreatic cancer. But for practical reasons, they often use a simpler system when trying to decide the best treatment. They may divide cancer into these 3 main groups based on whether they can be removed (resected) with surgery: